When I was a kid, back to school meant Labor Day in early September, and for most of the U.S. before the 1990s, that was true. But no more.

Data from MDR(a school data and marketing company)shows that “…roughly 25% of schools open sometime between Aug. 1 and Aug. 15 and another 25% beforeAug. 31. Though every state has a number of early and late opening schools, early openings are concentrated largely in the South (AL, GA, KY, LA, MS, TN) and Midwest (IN, MO, OK, NE) along with AZ, HI, NM an...